The objectives of the project are to study 1) the physiology of spirochetes which inhabit the body of humans and other mammals, and 2) the physiological factors and interactions that function in symbioses or associations involving mammalian hosts, spirochetes and other microorganisms. The results of these investigations are expected to provide information on the fundamental properties of pathogenic and non-pathogenic spirochetes, and to be useful in clarifying aspects of infectious processes in which spirochetes are involved. The project includes investigations on the energy-yielding pathways and amino acid metabolism of spirochetes indigenous to humans and other mammals. The biochemical bases of spirochetal cell coiling and the factors affecting cell coiling will be studied, inasmuch as cell coiling plays a role in the ability of spirochetes to migrate through environments of viscosity comparable to that of human cell membranes. Physiological interactions between spirochetes and other microorganisms indigenous to mammalian hosts will be investigated. Studies on the motility and chemotaxis of spirochetes are planned.